Oxides of amino acids



wherein dialkylamino 5 hydrocarbon radical having a Patented May 30,1939 UNITED STATES PATENT OFFICE OXIDES OF AMINO ACIDS Max Engelmann,

E. I. .du Pont de Nemours & Company, a corporation of DelawareApplication April 15, 1938, erial No. 202,358

mlngton, DeL,

No Drawlnms 13 Claims. (01. Zeb- 404) This invention relates to new anduseful surface active materials. More particularly it relates to newpentavalent nitrogen compounds containing acidic groups which aresuperior to soap and 5 soap substitutes. Still more particularly itrelates to di-alkyl-oxamino long chain fatty acids and the salts thereofand processes for preparing the same. r

It is an object of this invention to produce new and useful surfaceactive materials which may be substituted for or'used in admixture withvarious soaps and soap substitutes. A still further object is to producenew products which overcome many of the disadvantages of soap and soapsubstitutes.

The above and other objects are accomplished in accordance with theherein described invention boxylic acids are reacted with oxidizingagents tov produce dialkyloxamino' aliphatic acids. The acids preparedmay be represented by the following general formula;

N*-Rl m t wherein R1 and R2 represent aliphatic or cyclo- 40 aliphatichydrocarbon radicals, and R3 is an allphatic hydrocarbon radicalcontaining an acidic group, e. g., a carboxylic or sulfonic acid group,least one of the radicals represented by R1, R2 and R3 must have a chainlength .of at least 8 45 carbon atoms.

In a more limited sense the invention pertains to penta'valent'nitrogencompounds containing-a carboxylic acid group having. the followinggeneral formula:

N-ilr-CO OM- RC 1 I wherein one of the Rs represents an aliphatic chainlength of carboxyl group of preceding paragraph may be replaced by asuiand detergent agents.

long chain aliphatic carcarbon an at least '1 atoms, R1 representsphatic or cycloaliphatic hydrocarbon radical conthan 6 carbon atoms, andRa taining not more containing from 1 to 4 carbon is alkylene radicalatoms, and M represents hydrogen or a water soluble salt formingcomponent.

In another valuable form of this invention the the formula of theimmediately ionic acid group and the R attached to Rs is a hydrogenatom.

In its preferred embodiment this invention pertains to dialkyl-ox ocarboxylic acids and the salts thereof having the general formula:

wherein onefR is an alkyl radical containing at least '1 and preferably11 to 17 carbon atoms, and the other R is hydrogen and M representshydrogen or a water soluble salt forming component, e.-- g., alkali oralkaline earth metals and organic amines, such as diethylamin'e,triethanolamine,

etc.

The invention not intended to will be further illustrated but is belimited by the following examples in which the quantities stated are inparts by weight:

. Example I Thirty-one parts of alpha-dimethyl-aminostearicacid whichmay be prepared-by reacting alpha-brom-stearic acid and dimethyl-amine,12 parts of hydrogen-pe'roxide-urea compound (Beilstein Vol. III,'p. 54)and 150 parts of methyl alcohol are heated under reflux for 10 hours.The clear solution is then neutralized with 6 parts of a 20% aqueoussolution of sodium hydroxide and evaporated on a steam bath to dryness.The crystalline product is a mix ure of the sodium salt and the freedimethyl-oxamino-stearic acid.

It is easily soluble in warm water, forming a very L viscous solution.It is also soluble in methyl alcohol. Calcium or mangesium saltsolutions or acids or alkalies do not form insoluble precipitates inaqueous solutions. It is a very effective scouring agent.-

' Example II Fifty parts of alpha-dimethyl-amino-palmitic acid, 200parts of ethyl alcohol, and 50 parts of hydrogen peroxide (27% aqueoussolution), are boiled under reflux for l0.hours. After cooling, a smallpart of unreacted amino-acid is filtered oil, the filtrate neutralizedwith sodium hydroside solution and the alcohol evaporated on a steambath. The residue, containing dimethyl-' ox-amino palmitic acid, showsvery similar properties as the corresponding stearic acid derivative.

Example III Sixty parts'of ammonium persulfate are dissolved in 125parts of a 20% aqueous sulfuric acid solution and mixed with 50 parts ofalpha dimethyl-amino-stearic acid. The mixture, ,kept at roomtemperature, is slowly converted into a paste-like mass. After standingfor 48 hours, it is neutralized with 170 parts of 20% sodium hydroxidesolution. The resulting product is a gelatinous paste, containing asactive ingredient dimetirvl-oxamino-stearic acid.

In place of the specific oxidizing agents of the preceding examples anyof the usual types of oxidizing agents which are capable of liberatingfree oxygen may be used. Other agents which may be substituted are permono-sulfuric acid (Coros acid) organic peroxides, e. g.,benzoylperoxide, sodium hypochlorite, etc.

In place of the dialkyl-amino fatty acids of the preceding ,examples,any acid which complies withthe instructions set forth in the aboveformulae may be substituted. As further examples of such acids may bementioned diethyla-amino myristic acid, dimethyl e-amino palmitic acid,methyl-hydroxyethyl a-amino lauric acid, dibutyl a-amino capric acid.Mixtures of alkyl or hydroxyalkyl fatty acids obtained from natural oilsor fats such; as coconut oil, palm oil, lard, etc. The class ofcompounds may be prepared by alkylating a-amino long chain fatty acids,e. g., a-aminolauric acid, a-aminostearic acid a-methylamino palmiticacid, etc. with an alkylating agent in the usual manner, e. g., withmethyl or ethyl chloride, dimethyl sulfate, sodium butyl sulfate,ethylene oxide, propylene oxide, cyclohexyl chloride, etc.

Another series of dialkyl-amino long chain fatty acids which may be usedare those which may be prepared, for example, by reacting a long chainsecondary amine with a halogenated aliphatic acid, preferably acarboxylic acid. Amino acids of this type are methyl-stearyl-aminoaceticacid, propyl-lauryl-aminobutyric acid, octylhydroxyethyl amino-Valerieacid, methyl-decylaminoethane-sulfonic acid, ethyl heptadecylaminopropane sulfonic acid, etc.

The long chain radicals present in the oxamino acids can be derived fromanimal and vegetable oils or fats or from crude mineral oils (naphthenicacids) or from carboxylated or aminated natural or' synthetic long-chainhydrocarbons.

The uses of the compounds embraced within the scope of this applicationare legion and since i of a few uses will follow.

they are of chief value because of their surface active properties, nodetailed description here is deemed essential. However, in order toexemplify the value of the products in the arts, a mention For example,they may be used alone or in combination with other suitable detergentsfor cleansing and scouring vegetable and animal fibers when removingfatty or oily materials. They may be used as penetrants in acidsolutions which are used for carbonizing vegetable matter in wool. Whenadded to flax rotting baths, they function as wetting and penetratingagents. They may be employed as assistants in fulling and feltingprocesses. They may be used in sizing preparations in combination withthe usual materials such as starchesor gelaof stripping dyes from dyedments or pigments or azo,

tine or their. equivalents, clays, talcs or their equivalents, weightingsalts such as magnesium sulfate or calcium chloride, oils and oilsprocessed by oxidation, polymerization, sulfonation, etc. Thepenetrating power of these new compositions is utilized with advantagewhen they are added liquors used for mercerizing cotton goods. Theyimprove the absorption capability of fibrous materials when suchmaterials are subjected to treatments for finishing, softening,stiffening, coloring, preshrinking, impregnating, waterproof ing, andmildew-proofing. They may be used alone or in combination with othermaterials for lustering or delustering fabrics. They may be employed tooil or lubricate textile materials and as assistants in processes ofweighting or loading fabrics. They may be used as assistants in silkdegumming liquors and silk soaking solutions. They can also be used toassist in twist setting in yarn and in processes of stripping colors.These compounds may be used as assistants in processes textilematerials.

Another, important class of ,uses of these new compositions is asassistants in the preparation and application of dyestufis. They may beused in the preparation of dyestuffs in readily dispersible form and forthe production of inorganic pigbasic, acid, vat, and sulfur dyes in afinely divided condition. 'As penetrants and wetting agents they assistin producing level dyeings in neutral, acid or alkaline dyeing baths.They facilitatedyeing with developed dyes,

yeing of cellulose acetate fibers with insoluble dyes, dyeing andprinting with aniline black, and the dyeing of leather. In printingpastes they assist in the dispersion of the dye or dye component andfacilitate its penetration into the natural or synthetic fiber.Solutions of these compounds are useful for increasing the fastness ofdyeings on textile materials. Solutions of these compounds may be usedfor increasing the amnityof textile fibers of vegetable origin foracid-chrome dyestuifs. These compounds may be used as assistants'inresist printing processes.

In the leather industry these compositions function as useful wettingagents in soaking, deliming, hating, tanning, and dyeing baths. They areuseful in softening and treating baths for hides and skins, particularlyin baths used for fat-liquoring leather and'in processes ofwaterproofing leathen. Solutions of these compounds are useful forpretreating leather prior to dyeing.

The dispersing and emulsifying powers of these new compositions giverise to many interesting uses. They may beutilized for converting liquidor solid substances normally insoluble in water, such as hydrocarbons,higher alcohols, pitches and pitchy substances into clear solutions orstable emulsions or dispersions. They are useful in preparing emulsionsof wax and wax-like compositions which are used as leather dressings orfloor polishes. They may be used to prepare artificial dispersions ofcrude, ized or reclaimed water in such organic solvents as are usedinthe dry cleaning industry. They are also of value in the breaking ofpetroleum emulsions, such as those naturally occurring in nature orproduced during the refining of petroleum.

These compositions bactericides and contact insecticides and for onhancing the spreading and penetrating power of other parasiticides. Theymay be employed in agricultural sprays in combination with the ordinaryinsecticides and fungicides. They are useful for promoting thepenetrating power of wood preservatives.

In the paper industry these products may be used as penetrants in theliquors used for cocking rags and pulp, and as assistants in papersoftening, filling, and processes to increase absorbency.

These compositions may be employed as detergents in several differentrelations. They may be used in the washing of fruits and vegetables forspray residue removal. They may be used in combination with metalcleaning compounds in neutral, acid, or alkaline liquors. They may beused for paints, varnish, and lacquer cleaners.

. They may advantageously be employed as cleans.-

7 primary interest compounds may where a fatty or a.

ing agents in hard water and oily film resists the. .ordinary cleansingmedi They may be added to soap in acid or hard water baths, since thesecompositions do not form precipitates so readily in hard and acidstabilizing agents, especially for use in air-foam fire extinguishingcompositions. They may be used to stabilize rubber later. They may alsobe .used as frothing and collecting agents in ore fictation processes,and in other processes such as the recovery of fixed oil from the oilsands. The uses mentioned will suggest many similar ones.

By means of the present invention a large class of new and commerciallyfeasible surface active materials has been rendered available for use.These compounds possess satisfactory colloidal properties and are ofparticular value for use in place of or in combination with soap andsoap substitutes. This invention is of considerable it are for the mostpart readily available at a relatively low cost. The large variety ofreactions which may be relied upon t considerable latitude in theselection of reactants and the conditions of reaction. Lihewisethe largenumber of compounds embraced within this category permit the selectionof individual members therein? for a wide variety of purposes. In otherwords, where high wetting and dispersing properties are the molecular,weight of these compounds may be lowered. ,On the other hand, wheredetergent properties are of the molecular weight or the be increased.

As many apparently widely diflerent embodimerits of this invention maybe made without demay also be used alone as wherein R1 be employed asfoam V 3 parting from the spirit and scope thereof, it is to beunderstood that the invention is not limited to the-specific embodimentsthereof except asdefined in the appended claims.

I claim: l. The new products /N-Ra' R: and R: represent a radicalselected from the group consisting of aliphatic and cycloaliphaticradicals, and R: is an aliphatic hydrocarbon radical containing anacidic group and at least one of the radicals represented by R1, R2 andR: has a chain length of at least 8 carbon of the formula:

atoms.

2. The new products of the formula:-

N-Bs a i wherein R1 and R: represent a radical selected from the groupconsistingoi aliphatic and cycloaliphatic radicals and R: is analiphatic hydro-- carbon radical containing a monobasic acidic group andat least one of the radicals represented by R1, R2 and R: has a chainlength of at least 8,

carbon atoms;

3. The new products of the formula:

N-Rr-X I B--C wherein R is an 7 carbon atoms, R1 is a hydrocarbonradical selected from the group consisting of aliphatic andcycloaliphatic hydrocarbon radicals containing not more than 6 carbonatoms, R: is an alkylene radical containing from 1 to d carbon atoms,and X is an acid group selected from the class consis' of sulionic dbowlic acid groups.

a. The new products all the formula -COOM a -om t i wherein one R isnit? radical containing at least '2 carbon atoms and the other It ishydrogen, R1 is a hydrocarbon radical selected from the group consist ofaliphatic and cycloaliphatic hydrbcif contng not more than 6carbon-atoms, he is a lone radical containing from 1 to 4. carbon etc,and M represents a of the group on ting of hydrogen and a water solublet to group. 5. The new products of the formula a N-ts coon wherein one Ris an 1 real containing at least '1 carbon atdms and the other R ishydrogen, R1 is a hydrocarbon radiwl selected from the group canals ofphatic and cycloaiiphatic hydrocarbon radicals contng not more than 6carbon atoms, and M reprnts a member of the group consisting oi hydrogenand a water salt forming group.

6. The new acts oi a n-ori oooin iormula alml radical containingat leastsoluble Y wherein one R is an alkyl radical containing at least 7 carbonatoms and the other R is hydrogen, R1 is an aliphatic hydrocarbonradical. containing not more than 6 carbon atoms, and M representswherein R1 and R2 represent a radical selected from the group consistingof aliphatic and cycloa member of the group aliphatic radicals, R: is analiphatic hydrocarbon radical containing an acidic group and at leastone of the radicals represented by R1, R2 and Ba has a chain of at least8 carbon atoms with an oxidizing agent.

8. The process. which comprises reacting an amino acid 01' the formulawherein R1 and R2 represent a radical selected from the group consistingof aliphatic and cycloaliphatic radicals, R3 is an aliphatic hydrocarbonradical containing an acidic group and at least one of the radicalsrepresents by R1, R2 and R: at least 8 carbon atoms with an oindizingagent containing free oxygen.

9. The process which comprises reacting an amino acid of the formula R,wherein R1 and R2 represent a radical selected from the group consistingof aliphatic and cycloaliphatic radicals, R: is an aliphatic hydrocarbonradical containing an acidic group and at least has a chain of at least8 soluble salt forming one oi the radicals represented by R1, R2 and Bacarbon atoms with a peroxide. w

10. The process which comprises reacting an amino acid of the formulawherein one B is an alkyl radical containing at least 7 carbon atoms andthe other R is hydrogen, R1 is a hydrocarbon radical selected from thegroup consisting of aliphatic and cycloaliphatic hydrocarbon radicalscontaining not more than 6 carbon atoms, and R2 is an alkylene radicalcontaining from 1 to 4 carbon atoms with an oxidizing agent containingi'ree oxygen.

' 11. The new products of the formula CHI I R 1- rcn--cooM R-CH1 whereinone R is an alkyl radical containing at least '7 carbon atoms and theother R is hydrogen,

and M represents a member of the group consisting of hydrogen and awater soluble salt forming group.

i 12. The new products of the formula wherein R is an alkyl-radica1containing from 11 to 17 carbon atoms and M represents a member of thegroup consisting of hydrogen and a water group.

13. Alpha-dimethyl-oxamino stearic acid which has the formula MAXENGEIMANN.

